Current Educational Reform in Japan is oddly captured with confused conceptions of "compulsory education." The Ministry of Education blankets such connotations of it, as a national budget system, mandated school curriculum, responsible partnership of school with community and accountabilities of local school board, in defense of vested national budget against decentralization promoted by prefectural governors. However, the extended usage of "problems of compulsory education" results in the confusion of educational policies. This is because the core issues of current reforms are not concerned about whether school education should be compulsory or not, but on the future design of the public education system. This paper displays some historical aspects of the concept of "compulsory education," in order to enlighten the reason why the issues of it are expanded and unclear. Indeed, most people have confused the concepts of "public education," "public school system," "general education," "compulsory education" and "national education." In pre-war days, the compulsory education system was not launched in the early stages of modernization, but in 1886, when the first educational minister, Arinori Mori, legally designed the public education (general education) system to be established in the nation state. His idea of the "compulsory education" was characteristic. Though it was legitimated by "national education" constructed with "general education" or "public education," its financial foundation was not based on a national budget but school fees were paid by parents. This system was reorganized just after his assassination. "Compulsory education" became a nationalistic regime through which people were educated to be loyal subjects and obedient to the nation. At this point, the national budget system obtained its legitimacy for the foundation of national education. In postwar reform, the legitimacy of "compulsory education" was placed on education as a human right under the renewed constitution, connecting it with the human right to live, while most people have not recognized its significance. Thus, the concept of "compulsory education" is a puzzle in contemporary debates of educational reform. This paper explores the complicated relationship of "compulsory education" to the national budget system, through rethinking about the historical process of the public education system in Japan. [This article was translated by Walter Dawson.] (Contains 1 note.)